Re: Trying out SCHED_BATCH

[Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>]

On Thu, 30 Dec 2004 07:28:35 +1100, Con Kolivas <kernel@kolivas.org> wrote:
> Maciej Soltysiak wrote:
> > Hi
> >
> > Con wrote:
> >
> >> Only the staircase scheduler currently has an implementation of
> >> sched_batch and you need 2 more patches on top of the staircase patch
> >> for it to work.
> >
> > Hmm, Is it feasable to write a sched_batch policy for the current linux
> > schedulers?
> 
> Yes.
> 
> The proper way to make a sched_batch implementation is more
> comprehensive than what is made for staircase to prevent a deadlock
> based on a batch task getting an important lock in the kernel and not
> being able to release it due to a sched_normal task being higher
> priority than it that is actually trying to get the lock. There is code
> in the staircase version to prevent this from happening but probably not
> complete enough in design to prevent everything. However it works and I
> haven't had any reports of lockups since I implemented the extra checking.
> 
> Would you like me to create a version like that? I don't have the time
> to try and make a more comprehensive solution and follow the debugging
> of such a beast.
> 
> > I mean, if there are people that want it bad, maybe it would be nice to
> > be able
> > to use a version of sched_batch that would work without the staircase
> > scheduler.
> > It is still experimental, right?
> 
> No it's not experimental. It is very stable and used in production systems.

Are you gointo  to push to Linus/Andrew ?

-- 
Paolo